Nautilus is a spiral staircase developed as a dynamic design statement for a residential refurbishment. The minimalist hollow stair is formed from 180 unique pieces of ply, CNC cut and assembled on site with no visible connections. Hidden within the stringer and core are over 300 oak dowels specified to keep the layers of ply from delaminating under tensile loads. Each tread is made up from 10 layers of 18mm thick plywood. The treads were assembled on site utilising the hollow nature of the stair to clamp and bolt the treads whilst the glue dried. Each step has been finished with a plywood insert designed to be removable and replaceable in case the client ever wanted a different finish.